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1.
Hautarzt ; 69(7): 576-585, 2018 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-29435597

RESUMO

Patient 1: After contact to a central European hedgehog (Erinaceus europaeus), a 50-year-old female with atopy developed erythrosquamous tinea manus on the thumb and thenar eminence of the right hand. The patient had previously been scalded by hot steam at the affected site. The zoophilic dermatophyte Trichophyton erinacei could be cultured from the hedgehog as well as from scrapings from the woman's skin. Antifungal treatment of the hedgehog was initiated using 2 weekly cycles of itraconazole solution (0.1 ml/kg body weight, BW). In addition, every other day enilconazole solution was used for topical treatment. The patient was treated with ciclopirox olamine cream and oral terbinafine 250 mg daily for 2 weeks, which led to healing of the Tinea manus .Patient 2: An 18-year-old woman presented for emergency consultation with rimmed, papulous, vesicular and erosive crusted skin lesions of the index finger, and an erythematous dry scaling round lesion on the thigh. The patient worked at an animal care facility, specifically caring for hedgehogs. One of the hedgehogs suffered from a substantial loss of spines. Fungal cultures from skin scrapings of both lesions yielded T. erinacei. Treatment with ciclopirox olamine cream and oral terbinafine 250 mg for 14 days was initiated which led to healing of the lesions. Identification of all three T. erinacei isolates from both patients and from the hedgehog was confirmed by sequencing of the internal transcribed spacer (ITS) region of the ribosomal DNA, and of the translation elongation factor (TEF)-1-alpha gene. Using ITS sequencing discrimination between T. erinacei strains from European and from African hedgehogs is possible. T. erinacei should be considered a so-called emerging pathogen. In Germany the zoophilic dermatophyte T. erinacei should be taken into account as causative agent of dermatomycoses in humans after contact to hedgehogs.


Assuntos
Ouriços , Tinha , Trichophyton , Adolescente , Animais , Arthrodermataceae/isolamento & purificação , Arthrodermataceae/patogenicidade , Feminino , Alemanha , Ouriços/microbiologia , Humanos , Pessoa de Meia-Idade , Tinha/diagnóstico , Tinha/microbiologia , Trichophyton/isolamento & purificação , Trichophyton/patogenicidade
2.
Gesundheitswesen ; 78(6): 367-72, 2016 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-26140578

RESUMO

Exercise programs do not belong to standard treatment within disease management programmes for diabetes mellitus type 2, up to now. For these reason the effects of a 10-week behaviour-oriented exercise programme have been evaluated focusing on change in activity behaviour and health-related qualitiy of life. 202 patients took part in the investigation. There were significant inbetween group differences in some aspects of the outcome parameters. The study presents useful information on how to modify existing DMPs successfully for improving patient treatment.


Assuntos
Terapia Cognitivo-Comportamental/estatística & dados numéricos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício/estatística & dados numéricos , Promoção da Saúde/estatística & dados numéricos , Qualidade de Vida/psicologia , Adulto , Idoso , Terapia Combinada/psicologia , Terapia Combinada/estatística & dados numéricos , Diabetes Mellitus Tipo 2/psicologia , Terapia por Exercício/psicologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
3.
Radiologe ; 55(11): 992-4, 996-9, 2015 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-26293601

RESUMO

BACKGROUND: In clinically suspected fractures taking radiographs is the standard procedure but the indications should be strictly limited. Ultrasound offers a safe and radiation-free alternative for fracture diagnostics. OBJECTIVES: Sensitivity and specificity of sonographic fracture diagnostics and safety of sonographic algorithms for fracture evaluation. METHODS: Presentation of useful applications for sonographic fracture evaluation and establishment of sonographic algorithms for safe fracture diagnosis. RESULTS: In children distal forearm fractures can be diagnosed solely by ultrasound (sensitivity 96 % and specificity 97 %). The sonographic fat pad sign (SOFA) has been proven to be a useful primary screening tool for occult fractures of the pediatric elbow. A positive fat pad sign (SOFA+) is indicative of a fracture and radiographic diagnostics are necessary (sensitivity 97 % and specificity 91 %). Ultrasonography is also useful to exclude subcapital humeral fractures (sensitivity 94 % and specificity 100 %) and for correct estimation of displacement when present. CONCLUSIONS: Sonographic algorithms for fracture evaluation (SAFE) offer a safe diagnosis and guidance of the therapeutic course of certain pediatric fractures, thereby reducing unnecessary radiation exposure.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Algoritmos , Fraturas Ósseas/diagnóstico por imagem , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Adolescente , Criança , Pré-Escolar , Medicina Baseada em Evidências , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
4.
Unfallchirurg ; 118(12): 1070-1, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25986768

RESUMO

This report describes a case of complete rupture of the peroneal nerve as a consequence of low velocity trauma. A 54-year-old physically fit patient suffered a complex trauma with complete nerve discontinuity as a result of knee joint distortion without external force. The initial medical findings were unremarkable, in particular neither the accident medical history nor the initial sensitivity impairment suggested the presence of serious knee damage; however, during clinical diagnostics a complex trauma with rupture of the peroneal nerve was found. Accordingly, an extensive revision with nerve suturing was carried out.


Assuntos
Luxação do Joelho/complicações , Luxação do Joelho/cirurgia , Traumatismos dos Nervos Periféricos/etiologia , Traumatismos dos Nervos Periféricos/cirurgia , Nervo Fibular/lesões , Ruptura/cirurgia , Diagnóstico Diferencial , Humanos , Luxação do Joelho/diagnóstico , Masculino , Pessoa de Meia-Idade , Traumatismos dos Nervos Periféricos/diagnóstico , Nervo Fibular/cirurgia , Ruptura/diagnóstico , Ruptura/etiologia , Resultado do Tratamento
5.
Unfallchirurg ; 117(4): 355-68, 2014 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-24700086

RESUMO

X-rays are the standard imaging procedure for the diagnosis of pediatric long bone fractures. Recent studies show that ultrasound (US) imaging is also qualified to diagnose pediatric long bones fractures. Thus, the diagnosis and decision-making for the treatment of metaphyseal forearm fractures in children can be performed by solely using US. The sonographic fat pad sign has been proven to be a useful primary screening tool for pediatric elbow injuries. If there is a negative fat pad sign, a fracture is unlikely and taking additional radiographs is dispensable at this time. If there is a positive fat pad sign, a fracture is likely and radiographs should be taken. US is also useful to exclude subcapital humeral fractures and to estimate fracture displacement. If a fracture of the subcapital humerus is present, additional radiographs are necessary to avoid overlooking of pathologic fractures. For reliable sonographic fracture diagnosis in childhood, a detailed history und exact clinical examination are required.


Assuntos
Lesões no Cotovelo , Articulação do Cotovelo/diagnóstico por imagem , Fraturas do Úmero/diagnóstico por imagem , Aumento da Imagem/métodos , Fraturas do Rádio/diagnóstico por imagem , Fraturas da Ulna/diagnóstico por imagem , Ultrassonografia/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Posicionamento do Paciente/métodos
6.
Chaos ; 22(3): 037101, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23020492

RESUMO

Pattern forming instabilities are often encountered in a wide variety of natural phenomena and technological applications, from self-organization in biological and chemical systems to oceanic or atmospheric circulation and heat and mass transport processes in engineering systems. Spatio-temporal structures are ubiquitous in hydrodynamics where numerous different convective instabilities generate pattern formation and complex spatiotemporal dynamics, which have been much studied both theoretically and experimentally. In parallel, reaction-diffusion processes provide another large family of pattern forming instabilities and spatio-temporal structures which have been analyzed for several decades. At the intersection of these two fields, "chemo-hydrodynamic patterns and instabilities" resulting from the coupling of hydrodynamic and reaction-diffusion processes have been less studied. The exploration of the new instability and symmetry-breaking scenarios emerging from the interplay between chemical reactions, diffusion and convective motions is a burgeoning field in which numerous exciting problems have emerged during the last few years. These problems range from fingering instabilities of chemical fronts and reactive fluid-fluid interfaces to the dynamics of reaction-diffusion systems in the presence of chaotic mixing. The questions to be addressed are at the interface of hydrodynamics, chemistry, engineering or environmental sciences to name a few and, as a consequence, they have started to draw the attention of several communities including both the nonlinear chemical dynamics and hydrodynamics communities. The collection of papers gathered in this Focus Issue sheds new light on a wide range of phenomena in the general area of chemo-hydrodynamic patterns and instabilities. It also serves as an overview of the current research and state-of-the-art in the field.

7.
Chaos ; 22(3): 037112, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23020503

RESUMO

A combined study devoted to chemo-Marangoni convection and the underlying kinetics is presented for a biphasic system in which surfactants are produced in situ by an interfacial reaction. The pattern formation studied in a Hele-Shaw cell in both microgravity and terrestrial environments initially shows an ensemble of chemo-Marangoni cells along a nearly planar interface. Soon, a crossover occurs to periodic large-scale interfacial deformations which coexist with the Marangoni cells. This crossover can be correlated with the autocatalytic nature of the interfacial reaction identified in the kinetic studies. The drastic increase in the product concentration is associated with an enhanced aggregate-assisted transfer after the critical micellar concentration is approached. In this context, it was possible to conclusively explain the changes in the periodicity of the interfacial deformations depending on the reactant concentration ratio.

8.
J Hous Elderly ; 26(1-3): 275-289, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25214701

RESUMO

This paper focuses on stigma in collective living environments for older adults, specifically multi-level campuses. We contrast two design profiles, a purpose-built campus which opened in 1997, and an older setting that grew by accretion over decades. Purpose-built housing is used as originally intended, designed, and constructed; housing built by accretion has been modified over time to meet changing needs and uses. The separation by care levels in both sites is reflected in their cultures as residents and staff relate to physical levels of care through a vocabulary of fear and stigma. Residents of the independent living building on the purpose-built campus refer to the assisted living building, accessed only through a second floor link, as "the other side" or "the dark side." In this setting we observe stigma assigned to a place in the built environment. By contrast, in the older setting built by accretion over the last century, levels of care feature a less-structured clustering of independent living and assisted living, and common areas were shared by residents from multiple care levels. We have observed less stigma associated with levels of care in this older building. Grounding our analysis in data drawn from ongoing ethnographic research, we focus on the built environment as it relates to stigma in the social environment. The paper concludes with a discussion of the importance and pervasiveness of stigma in senior environments.

9.
J Phys Condens Matter ; 51(1)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36279867

RESUMO

The liquid fraction of foam is an important quantity in engineering process control and essential to interpret foam rheology. Established measurement tools for the liquid fraction of foam, such as optical measurement or radiography techniques as well as weighing the foam, are mostly laboratory-based, whereas conductivity-based measurements are limited to the global measurement without detailed spatial information of liquid fraction. In this work, which combines both types of measurement techniques, the conductivity-based wire-mesh sensor is compared with neutron radiography. We found a linear dependency between the liquid fraction of the foam and the wire-mesh readings with a statistical deviation less than 15%. However, the wire-mesh sensor systematically overestimates the liquid fraction, which we attribute to liquid bridge formation between the wires.

10.
Br J Cancer ; 105(3): 445-51, 2011 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-21750551

RESUMO

BACKGROUND: The aim of this longitudinal study was to determine age- and sex-standardised prevalence rates of cancer-related fatigue in different groups of patients. METHODS: This was a prospective study in a cohort of N=1494 cancer patients investigating fatigue at three time points t1-t3 (t1: admission to hospital, t2: discharge, t3: half a year after t1). Fatigue was measured with the Multidimensional Fatigue Inventory. Age- and sex-adjusted norms were derived from a representative community sample of N=2037, using a cutoff at the 75th percentile. RESULTS: At admission to the hospital, 32% of the patients were classified as fatigued. At discharge, the overall prevalence rate was 40%, and at half a year after t1, prevalence was 34%. Fatigue prevalence rates differed according to tumour stage, site, age, and sex of the patients. CONCLUSION: The prevalence rates provided by this study can be used for the planning of research and clinical routine.


Assuntos
Fadiga/epidemiologia , Neoplasias/epidemiologia , Adulto , Fatores Etários , Hospitalização , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Neoplasias/complicações , Prevalência , Estudos Prospectivos , Fatores Sexuais
11.
Unfallchirurg ; 113(10): 839-42, 844, 2010 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-20865237

RESUMO

AIM OF THE STUDY: The exact determination of the extent of deformities in juvenile proximal humerus fractures is difficult with plain x-rays. The aim of this study was to find out whether proximal humerus fractures can be diagnosed and the extent of the deformity can be detected by ultrasonography. PATIENTS AND METHODS: In a prospective, multicentre trial children aged 0-12 years with suspected proximal humerus fractures were examined. Initially a standardized sonographic evaluation was performed and the extent and the direction of the deformity were determined. The recommended treatment was noted. Afterwards standard x-rays were taken and the results of both diagnostic procedures were compared. RESULTS: A total of 33 children were examined, 14 male and 19 female, with a mean age of 7.6 years. In the ultrasound examination 17 out of 18 proximal humerus fractures were detected. In comparison to x-ray diagnostics ultrasonography proved to have a sensitivity of 94% and a specificity of 100%. In 16 cases ultrasonography gave a better result than x-ray imaging and x-ray was better in 5 cases. CONCLUSION: Ultrasonography is suitable for detection and exclusion of fractures and better than x-ray diagnosis for evaluation of the type and direction of deformations of proximal humerus fractures.


Assuntos
Fraturas do Ombro/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Radiografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia
12.
Phys Rev E ; 101(6-1): 062601, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32688567

RESUMO

The deformation of the free surface of a paramagnetic liquid subjected to a nonuniform magnetic field is studied. A transient deformation of the surface caused by the interplay of gravity, magnetic field, and surface tension is observed when a permanent magnet is moved vertically downward to the free surface of the liquid. Different concentrations of rare-earth-metal salt (DyCl_{3}) are used and different magnet velocities are studied. The deformation of the interface is followed optically by means of a microscope and recorded with a high-speed camera. The experimental results are compared and discussed with complementary numerical simulations. Detailed results are given for the static shape of the deformed surface and the temporal evolution of the surface deformation below the center of the magnet. The frequency of the surface oscillations is found to depend on the concentration of the salt and is compared with analytical findings. Finally, a potential application of the effects observed is presented.

13.
Transfus Med ; 19(1): 43-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19302454

RESUMO

The objective of this study was to determine if clinically important thromboembolic adverse events (TAEs) because of recombinant activated factor VII (rFVIIa) administration are being under-reported. rFVIIa is a potent haemostatic agent with a short half-life of 2.6 h that is increasingly used in 'off-label' situations. Retrospective review of 94 patients who received rFVIIa during 1 January 2003 to 30 June 2007 was carried out at a tertiary care centre. Sixty-nine patients, 32 females and 37 males, mean age 55 years (18-84 years), satisfied study criteria of off-label usage. This was a high-risk population with 33 (48%) deaths. A mean dose of 8.2 mg (2.4-19.2 mg) was administered in two average divided doses. Thirty-six potential TAEs were identified in 29 patients, and of these, 12 patients had TAEs deemed to be rFVIIa related and were identified on average 8.8 days after exposure to rFVIIa. Forty-eight (70%) physician questionnaires were completed; however, no TAEs were reported in these questionnaires or on chart review. Potential clinically significant TAEs are being under-reported by treating physicians. Until further evidence, we suggest the urgent need to develop consensus recommendations for utilization and required follow up to monitor the safety of rFVIIa and that at a minimum, all use of rFVIIa should be regulated through a gate-keeping mechanism that ensures adherence to these policies. Furthermore, prospective registries and trials are necessary to evaluate the efficacy and safety of rFVIIa in off-label settings.


Assuntos
Fator VIIa/efeitos adversos , Gestão de Riscos/estatística & dados numéricos , Tromboembolia/induzido quimicamente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Médicos , Proteínas Recombinantes/efeitos adversos , Estudos Retrospectivos , Inquéritos e Questionários , Taxa de Sobrevida , Adulto Jovem
14.
Lab Anim ; 43(2): 182-90, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19246505

RESUMO

The manner in which an animal's environment is furnished may have significant implications for animal welfare as well as research outcomes. We evaluated four different housing conditions to determine the effects of what has been considered standard rodent enrichment and the exercise opportunities those environments allow on disease progression in the amyotrophic lateral sclerosis mouse model. Forty-eight copper/zinc superoxide dismutase mice (strain: B6SJL-TgN [SOD1-G931]1Gur) (SOD1) and 48 control (C) (strain: B6SJL-TgN[SOD1]2Gur) male mice were randomly assigned to four different conditions where 12 SOD1 and 12 C animals were allotted to each condition (n = 96). Conditions tested the effects of standard housing, a forced exercise regime, access to a mouse house and opportunity for ad libitum exercise on a running wheel. In addition to the daily all-occurrence behavioural sampling, mice were weighed and tested twice per week on gait and Rotor-Rod performance until the mice reached the age of 150 days (C) or met the criteria for our humane endpoint (SOD1). The SOD1 mice exposed to the forced exercise regime and wheel access did better in average lifespan and Rotor-Rod performance, than SOD1 mice exposed to the standard cage and mouse house conditions. In SOD1 mice, stride length remained longest throughout the progression of the disease in mice exposed to the forced exercise regime compared with other SOD1 conditions. Within the control group, mice in the standard cage and forced exercise regime conditions performed significantly less than the mice with the mouse house and wheels on the Rotor-Rod. Alpha motor neuron counts were highest in mice with wheels and in mice exposed to forced exercise regime in both mouse strains. All SOD1 mice had significantly lower alpha neuron counts than controls (P < 0.05). These data show that different enrichment strategies affect behaviour and disease progression in a transgenic mouse model, and may have implications for the effects of these strategies on experimental outcomes.


Assuntos
Esclerose Lateral Amiotrófica/fisiopatologia , Abrigo para Animais , Condicionamento Físico Animal/fisiologia , Esclerose Lateral Amiotrófica/patologia , Animais , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Marcha/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Motores/fisiologia , Distribuição Aleatória , Medula Espinal/patologia
15.
Unfallchirurg ; 112(8): 706-11, 2009 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-19280166

RESUMO

BACKGROUND: Metaphyseal forearm fractures are a common pathology in any emergency department. The standard diagnostic procedure involves X-rays of the forearm and wrist. As former studies have shown that these fractures can be visualized using ultrasound, we compared the accuracy of sonographic and X-ray diagnostics. METHODS: From January 2007 to May 2008, a total of 93 patients aged between 0 and 12 years with forearm trauma were initially examined using a 7.5-Mhz linear transducer. After diagnosis, axis deviation and treatment were fixed and standard X-rays were taken. The results of the two diagnostic procedures were compared. The examiners were doctors in training or consultants and underwent no specific training. RESULTS: We found 77 fractures in 64 patients (50 radius, 1 ulna, 13 radius and ulna). The sensitivity of ultrasound diagnostics was 94% and the specificity 99% compared with X-ray diagnosis. Mean axis deviation differences were 1.8 degrees (radius) and 0.7 degrees (ulna). CONCLUSION: Ultrasound seems to be a valuable and safe alternative to X-ray diagnosis. Patients with inconclusive findings should undergo X-ray diagnosis.


Assuntos
Traumatismos do Antebraço/diagnóstico por imagem , Fraturas do Rádio/diagnóstico por imagem , Fraturas da Ulna/diagnóstico por imagem , Criança , Feminino , Alemanha , Humanos , Masculino , Microscopia Acústica , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Urologe A ; 56(3): 351-357, 2017 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-27637182

RESUMO

BACKGROUND: Removing boys' foreskins, even for medical reasons, is increasingly and critically discussed. The aim of this study is to retrospectively verify if the indication for the removal of boys' foreskins was justified. The study is based on the records of boys who underwent preputial operation in an outpatient medical office for pediatric surgery. METHODS: Preoperative clinical findings, complaints, applied conservative and/or surgical procedures and histological results of the resected foreskins of boys, who underwent preputial operation between 2013-2015, were retrospectively analyzed. RESULTS: A total of 176 boys (age 5 on average) underwent a preputial operation. In 85 % of the cases it was completely removed. Most frequent clinical findings (80 %) were that the prepuce was simply not retractable. 86 % of the boys were free of complaints. The most frequent histological findings were a discrete to moderately pronounced chronic fibrous posthitis (69 %) and subepithelial fibrosis (18 %), In the first case 78 % of the boys had been free of complaints, in the latter 72 %. CONCLUSION: The majority of the treated boys were free of complaints; however, most of them underwent a complete removal of their foreskin simply because it was nonretractable. The foreskin represents the most sensitive part of the male genital, preputiolysis is a natural process that can go on until early adolescence. Irreversible surgical procedures, such as a complete foreskin removal, should thus be restricted to a clear medical indication.


Assuntos
Circuncisão Masculina/estatística & dados numéricos , Prepúcio do Pênis/cirurgia , Assistência Centrada no Paciente/métodos , Fimose/epidemiologia , Fimose/cirurgia , Doenças Assintomáticas/epidemiologia , Doenças Assintomáticas/terapia , Pré-Escolar , Tomada de Decisão Clínica/métodos , Autoavaliação Diagnóstica , Humanos , Masculino , Seleção de Pacientes , Fimose/diagnóstico , Prevalência , Estudos Retrospectivos , Resultado do Tratamento
17.
Nucleic Acids Res ; 28(14): 2831-8, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10908342

RESUMO

Mutagenesis at [GT/CA](10), [TC/AG](11) and [TTCC/AAGG](9) microsatellite sequences inserted in the herpes simplex virus thymidine kinase (HSV-tk) gene was analyzed in isogenic mutL(+) and mutL(-) Escherichia coli. In both strains, significantly more expansion than deletion mutations were observed at the [TTCC/AAGG](9) motif relative to either dinucleotide motif. As the HSV-tk coding sequence contains an endogenous [G/C](7) mononucleotide repeat and approximately 1000 bp of unique sequence, we were able to compare mutagenesis among various sequence motifs. We observed that the relative risk of mutation in E.COLI: is: [TTCC/AAGG](9) > [GT/CA](10) approximately [TC/AG](11) > unique approximately [G/C](7). The mutation frequency varied 1400-fold in mutL(+) cells between the tetranucleotide motif and the mononucleotide motif, but only 50-fold in mutL(-) cells. The [G/C](7) sequence was destabilized the greatest and the tetranucleotide motif the least by loss of mismatch repair. These results demonstrate that the quantitative risk of mutation at various microsatellites greatly depends on the DNA sequence composition. We suggest alternative models for the production of expansion mutations during lagging strand replication of the [TTCC/AAGG](9) microsatellite.


Assuntos
Adenosina Trifosfatases , Repetições de Dinucleotídeos/genética , Proteínas de Escherichia coli , Escherichia coli/genética , Repetições de Microssatélites/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Pareamento Incorreto de Bases , Reparo do DNA , DNA Recombinante/genética , Proteínas MutL , Mutação , Plasmídeos , Simplexvirus/enzimologia , Timidina Quinase/genética
18.
Cancer Res ; 60(6): 1698-703, 2000 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10749142

RESUMO

We have examined mutational events at TC/AG microsatellites, the second most abundant dinucleotide repetitive motif in the human genome. Mutational targets were constructed containing TC/AG alleles up to 20 units in-frame within the coding region of the herpes simplex virus thymidine kinase (HSV-tk) gene. These targets were incorporated into oriP shuttle vectors, which replicate episomally in human lymphoblastoid cells. The overall HSV-tk mutant frequencies measured after 10 population doublings in cells derived from a clinically normal donor were slightly increased over the background of mutations recovered in Escherichia coli. DNA sequence analyses revealed that replication of TC/AG vectors in human cells increased the mutation frequencies at the microsatellite motif up to 3-fold, relative to background. Additionally, the median HSV-tk mutation rate of single-cell clones carrying the [TC/AG]17 vector was significantly different from that of clones harboring the control vector. The median rate of allele length alterations within the [TC/AG]11 tract was 2 x 10(-6) mutations/cell generation, with an equivalent rate of deletion and expansion mutations. In contrast, a [GT/CA]10 vector showed no increase in microsatellite mutation frequency after replication in human cells, and mutation rates of clones carrying a [GT/CA]16 vector were not significantly different from controls. Intriguingly, replication in human cells of all microsatellite-containing vectors resulted in elevated mutation frequencies at the downstream HSV-tk coding sequence of up to 20-fold, an effect not observed for the control vector. These results demonstrate that the frequency of mutational events at TC/AG motifs is slightly greater than at GT/CA motifs of similar allele length. This is the first report to our knowledge of the mutation rates at TC/AG microsatellite alleles in eukaryotic or prokaryotic cells.


Assuntos
Linfócitos/metabolismo , Repetições de Microssatélites/genética , Mutação , Sequência de Bases , Linhagem Celular Transformada , Replicação do DNA , DNA Recombinante/genética , Repetições de Dinucleotídeos/genética , Escherichia coli/genética , Frequência do Gene , Vetores Genéticos/genética , Humanos , Linfócitos/citologia , Proteínas Recombinantes de Fusão/genética , Análise de Sequência de DNA , Deleção de Sequência , Simplexvirus/enzimologia , Timidina Quinase/genética
19.
Cancer Res ; 50(3): 642-7, 1990 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-2297705

RESUMO

A tumor-associated epidermal growth factor (EGF)-like activity was detected in the urine of breast cancer patients by means of an EGF radioreceptor assay and an anchorage-independent growth assay. The clonogenic growth factor activity of pooled void volume eluate fractions from a Bio-Gel P-30 column was completely neutralized by an anti-human epidermal growth factor antiserum but not by an anti-transforming growth factor alpha antiserum. This activity was determined in the urine of 71 breast cancer patients. A statistically significant correlation was found between EGF-like clonogenic activity and axillary lymph node status, tumor size, stage of disease, and grade of differentiation of the primary tumor. The Bio-Gel P-30 void volume fraction was used to purify the EGF-related polypeptide to apparent homogeneity by subsequent binding to and elution from A431 cells followed by isoelectric focusing. A polypeptide of a pI of approximately 3.4 was identified to be related to EGF by neutralization and immunoprecipitation experiments with anti-human epidermal growth factor antisera. This polypeptide migrated as a single band of Mr 43,000 in sodium dodecyl sulfate-polyacrylamide gel electrophoresis.


Assuntos
Neoplasias da Mama/urina , Substâncias de Crescimento/urina , Bioensaio , Cromatografia em Gel , Reações Cruzadas , Fator de Crescimento Epidérmico/imunologia , Substâncias de Crescimento/imunologia , Substâncias de Crescimento/isolamento & purificação , Humanos , Ponto Isoelétrico , Peso Molecular , Testes de Precipitina
20.
J Phys Chem Lett ; 7(3): 520-4, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26789535

RESUMO

We report on the first experimental evidence of a self-pinning liquid drop on a liquid surface. This particular regime is observed for a miscible heavier oil drop (dichloromethane) deposited on an aqueous solution laden by an ionic surfactant (hexadecyltrimethylammonium bromide). Experimental characterization of the drop shape evolution coupled to particle image velocimetry points to the correlation between the drop profile and the accompanying flow field. A simple model shows that the observed pinned stage is the result of a subtle competition between oil dissolution and surfactant adsorption.

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